US1617594A - Relay - Google Patents

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US1617594A
US1617594A US474542A US47454221A US1617594A US 1617594 A US1617594 A US 1617594A US 474542 A US474542 A US 474542A US 47454221 A US47454221 A US 47454221A US 1617594 A US1617594 A US 1617594A
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armature
relay
contacts
current
movement
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US474542A
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Clinton O Harrington
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ALDOBILT Co
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ALDOBILT Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00Details of electromagnetic relays
    • H01H50/16Magnetic circuit arrangements
    • H01H50/18Movable parts of magnetic circuits, e.g. armature
    • H01H50/34Means for adjusting limits of movement; Mechanical means for adjusting returning force

Description

Feb. 15, 1927.
C. o. HARRINGTON RELAY Fiaed Juris 2. 1921 2 sheets-sheet '1.
Feb. 15,192'f1z. 1,617,594
C. O. HARRINGTON` n I vRELAY Filed Juize 2. 192i 2 Sheets-Sheet '2 ifo/f1. Co2. 2,. COLD', Col.1. C0116.
fl@ Nil M355.' M0-ff l@ Panta ra. 15, 1927. Lerner PATENT OFFICE.
CLINTON 0.*HARRINGTON, OF CHICAGO, ILLINOIS, VASSIGrlOR 'IO ALDOBILT COMPANY,
OF CHICAGO, ILLINOIS, A. CORPORATION OF ILLINOIS.
RELAY.
Application flled June 2", 1921. Serial No. 474,542.
v My invention relatesto relays. One of `ed prior to installation for use in connection its ,importantl objects isto `r-*ovide a 'relay with a predetermined current, and, later, according to which,V at `pic up current, al should afurther adjustment be required, the suitable pressure between the make-ande' device would be removed from service and breal; contacts will. be automatically, pro? taken baclrto the shop. vided throughout thenormal 'and s'ub'st'an According to the present improvements tiallylarge range of adjustmentof the air-l the 'desired adjustments'may bev made in a gap `in the magnetic circuit; According "to verybrief space of time'j without removing the speciiic device 'illustrated herein this the relay from service, and withoutthe use flu c0ntactfpressure`issubstantially uniform at ot auxiliary measuring means. G0
the several adjustments of the. air` gap, A further object is to provide a relay havamong the advantages'vof Vwhich is substan-l ing means forv readily varyingin predetertial j uniformity' in electrical resistance at mined'amounts the magnetizing force ot the the contacts( j magnet coils which is produced by a given r15 Another important'object is to providel currentf'available for operating the relay.- 65
' meansjin asso'ciationwith a relay for indi- According to this i'eature ifi the current k'eating the amount of adjustment obtained, available at a. particular placebe either too both' of the air gaptin 4the speciiic,device-'large or 'too small for operating the relay shown) and of the contact"fopening,:where- Vwithin the limits of adjustment of the air 20 by the use of specialA measuring:instruments gap" andat a given arrangement of the cur- 70 is avoid-ed inmaking thel desired adjust- Vrent Iflow,"the iiow of the l' current to the ments, and. whereby, upon determining the magnet coil or coils may be so varied as'to current for whichthe instrument-iis to be produce al lesser or greater magnetizingadusted, the yadjustment ofboth the air gap torce, and thereby bring the availablecur 25 and the contact opening7 may `be made for rent witliiutlie limits ot adjustmentof the 75 that currentin a simple andA expeditiousair gap. wayaccordingto indicator means associated Other objects and advantages will appear with the device. .Y hereinafter. l Accordingto the illustrated specific em- Inthe 'accompanying drawings, which bodiment tot "the present inven'tion-a'single form apart oty this specification, Figure l 80 adjustment made according` to a single read'- is a` vertical section through the magnet ing. ot theiiidicator simultaneously'adjusts I cores and other parts ot my improved relay the air gap and the contactv opening in their as it is normally positioned for use; Fig. 2 proper relation to eachother. 1s Va horizontal section on the line 2-2 ot It has heretofore been lsuggested to employ Fig. l; Fig.` 3 is a top plan of `the device; 85 in' a relay means for adjustably varying an and Fig. 4 is an enlarged vtace view ot' a air ,gap in the magnetic circuit, together form of chart` which may accompany-thedewith independent means for adjustingcthe vice and which shows the operating current distance between the contacts.` According at various adjustments oty the instrument.
40 to such a rela ot the )rior art the Yadpuster The base 10 of my im Droved rela i is Y ...l l l 5 90 ot the 'instfument,A bycarefu'land 'painstak shown as a rectangular piece ot insulating Y ingiworlr in. the nature of lte'sts and experimaterial such yas porcelain.l 'The .magnet mentations, could secure appropriate adjustcores 1l,l the back strap 12 and the magnet ments ot both the air gap and of the contacts windings 13 are to Ybe understood as being throughout the adjustment`range, but such according to well-known construction. The 95 anadju'stment wouldbe exceed 4ngly difficult coresll terminate'in pole pieces` 14 which and substantiallyimpracticable in the iield are sho-wn as integral with the coresresp-ecat the time and place the 'adjustment is detively, are circular in :tace view, and each sired.Y In practice the` instrument ot the ot'which is eccentric to 'its' core axis where-- .to 91der'l5ad referee.taiwanais-be adjust by the Centers 0f the rolf-Pisces respectively 10Q are brought closer to each other, enabling the use of a shorter armature and reducing its weight and magnetic reluctance. The pole pieces and the cores are held on the base in their desired positions by screws 15.
The armature 16 is shown as a rectangular piece of flat iron hinged at 17 to the bracket 18 secured by 'screws 19 to vthe base 10. The armature carri-es a pair of threaded insulating studs 22 and these in turn support the cont-act member 23 consisting of a piece of sheet metal bent as indicated in Fig. 1 and to which is secured a thinner and more resilient member 24 having secured to it the contact tip 25. The contact meml er 23 is electrically connected by flexible wire 26 to the binding post 27 to which is secured the lead 28 for the current controlled by the relay.
The construction thus far described, while differing in minor respects from hitherto suggestions, is, as to function and result, in accordance with practice well known.
Upon the under side of the base is secured a metallic U-shaped bracket having a part 29 secured by screws 30 upon the base 10, a normally downwardly-extending part 31, and a horizontal part l32. Between and rigidly secured to the bracket parts 29 and 32 are two guiding-and-supporting rods 33 spaced apart and parallel to each other. Two rectangular metallic blocks or carriers and 36 are bored so as to lit slidingly upon the rods 33 as well illustrated in Fig. 1. The block 35 carries a support 37 which extends below the light-weight metallic enten-v sions 38 of the armature 16 and acts as a rest or stop which limits the gravitational movement of the armature away from the pole faces of the cores. The other movable block or carrier 36 carries a threaded insulating stud 39 upon which is positively held the small metallic bracket 4() carrying the contact plate 41 close to and above the contactV tip 25. The contact 4l is electrically connect-ed by a flexible wire 42 to the binding post 43 to which is secured the lead 44 for the current controlled by the relay. lt is thus clear that between the binding posts 27 and 43 there is a make-andbreak device including a contact controlled by the movement of the armature.
It is well understood in the art that by increasing or decreasing an air gap in the magnetic circuit the reluctance of the circuit is increased or decreased According to these improvements as specifically illustrated l provide means for adjustably varying the air gap between the armature 16 and the pole pieces 14 for varying this reluctance, thus increasing or decreasing the responsiveness of the armature to the magnetic energy whereby the armature will move toward the pole face in response to different values of the current coils.
In the specific device illustrated the air gap and the distance between the contacts are both varied adjustably by means for moving the carriers 35 and 36. F or this purpose I provide a. unitary shaft 45 which passes loosely through the base 10 and is journaled in the metallic bracket member 29 at a reduced diameter of the shaft 45, thus providing a shoulder which prevents longitudinal movement of the shaft in one direction. The reduced portion 46 of the shaft 45 is threaded and the carrier 35 is interittingly threaded whereby rotation of the shaft 45 will move the carrier 35 upon the guides 33. The shaft 45 has a further reduced portion 47, this latter portion being journaled in the bracketmember 32 and carrying the pinion 48, the shaft being riveted at 49 upon the pinion, the inner face of the pinion bearing against the surfaced boss 50 on the bracket member 32, the shaft 45 thus being maintained against longitudinal movement in the other direction from that above mentioned. This reduced portion 47 of the shaft is also threaded, with threads of the same direction as those on the part 46, and when the shaft 45 is rotated the carrier or block 36 is moved thereby through the action of a nut member 51 threaded upon the shaft portion 47 and held rigidly upon the carrier 36 when the device is in use. This nut member 51 comprises a hexagonal head, indicated by dotted lines in Fig. 2, and a cylindrical stem 52 rotatably journaled for preliminary adjustment purposes in the block 36 and having its inner edge spun over so as to overlie a portion of the block 36 whereby the nut member 51, 52 is permanently though rotatably retained in its operative position. In order that the relay may operate according to the chart provided as a guide to its future adjustments the ai r gap and the distance between the contacts must bc independently adjusted so that with a. given air gap thc pick-up and release current values will correspond to the chart for that air gap. A fte r this initial calilnaton has been made the nut member 5l is secured, as by soldering at 55, to vthe block 36.
Each block 35 and 36 is provided with aI recess facing the other and containing a coiled expansion spring` 5" adapted to mainpassing through the magnet o@ tain the blocks against lost motion or play with respect to each other. y
lt is here pointed out that the threads upon the part 46 of the shaft 45 are of greater pitch than those on the part 47 of this shaft. In my practice the shaft part 46 has thirty-six threads per inch and the shaft part 47 has forty-eight threads per inch, but the ratio of the respective thread pitches may Larrea-1A Vary according to A the construction y or arrangement ofI other features of the'device, as
' will hereinattermoretully appear.
.orl decreased, but in an amount which is less thanfwouid be the case ifthe contact as 41 Awere fixed. n
`the desired, relative movementbetween, the-carriers and 36 (determined by vr,the VCliffere-ncein pitch ,of vthe threads on the screw shaft 45). will depend partly uponr the distance from the armature pivotl to the point. where y,thearmature is supported in comparison with the distance vfrom. the same pivot to. the Contact QM'having considerati r` 1,oty thelditlerence in arcuate Vmovement dueto different ,radialleng'ths) I have providedi nieansr touadjusting this latter vratio wherebythe desired results Qta substantially' 1 uniform pressure between the contacts at the various air gap u'stments may be secured without enclusiye'reliance uponthe ratio of thethrean pitches on the screw shaft 45.
T hatis `to sayythe device may be constructed .withf the lratio onfthread pitches y hereinabove mentioned2 (namely 36 tofl8) or with a dit-I ferent ratio,l and, thouglrthe instrnment may be lconstructedwith a somewhat ditterentarrangement or proportion ot parts the desired result may be obtained adjusting the ratio between'the fetfectinvezradius of the armature andfthatfoit V'the contact' member carried by it.y In thespecitic device V'i llustrated-the rest or stop member 37 is longitudinally vslotted at and a mall round-headed boltl constitlttingthe stopI proper and held adjiistably inipl'ace Aby aI nut 62 isfv movable through` the slot6 0 `wherebythe radial distance from `the pivotflgfto, the button .61 .mayy be increased ordecreased, thus varying the ratio between this -iadiris and v .that ot 'the V contant 25. Witli .this provision lot adjustment it is merely a `matter of ordinary calibration to determine the relative position of theA stop button Accordingto these improvements the conpressuremay be *maintained substantially uniformthroughout awide range of adjustment of Vthe airgap', and vby the term substantially unitorm. .in .this connection I donotmeanfto exclude relatively small variations in pressure in both direct-ions from a givenx .inc an, such slight variations being sub.- stanti'ally ,inherent in any. construction of this-icharacter due to variations in materials and workin'anship-7` but which variations in a device e 1'nbodying the present invention are unimp'oigtantto the desired result. y
Means for turning the screw shaft 4 5 comprise ahand wheel 6 5. frict-ionallyk held uponV the reducedv stemt@ by the spring 6T' and nut 5 8.' .'I`liis drive isu'provided tov prevent daniagetof the threadswatt ande? or to. other parts through careless manipulation.` Means for holding the`screw shaft fl.
in a A desired position ol adjustment include a Vspring-pressed plunger (39"liaving a forwardlyV projecting' pin' 70 adapted tof enten any one of fourradifal equidistant'holes 7l' inthe shaftll, the pin 7() being retractible by means of its outwardlyprojecting end 72, the plunger beingcarried within ka casing 73 secured upon the base l0 asby a screw/'74 and the holding leffect of the shaft 45. IV hen the pin is'in locking'position the hole 75 in the rod @registers with thehole 7G through they casing member 73 whereby a wire may be passed through these parts'and sealed'ffor maintaining the Vadjustment made.
I also provideineans Afor indicatingvth'e l relative adjustments secured by turning' the screw shatftl, these means comprising the pinion 48 driven by theshaft 45 and meshing with thegear 8O journaled on the bracket arm 32"by a shouldered screw 8l. The
pointer82 is held also upon the screw 8l and is maintained against rotation by a locking pm 83.
The gear 8O is marked as a dial and its movengient`relative to the lined pointer 82 indicates thel adjustment of the several parts sin'iultaneously m`ade,` and, consequently the pick-'up and release values of the current passing through the magnetV coils.
In'FigLS I have shown, partly diagrammatic form`l a device mounted on'the'base l0 for adjustably varying,v inv predetermined amounts, the magnetizing torce of themagnet produced by a given current supply. Tothis end I provide a pair of binding postsA and'D to Awhiclithey lead wires 86 and 87 carryingthe current for energizing the magnet areconnected respectively. I also provide binding 'posts C, E and'B so located that a coinn'ioninetalli'c conductor 88 may be connected between the binding posts A and C and between the posts C and E and between the posts@ and B and also betweenthe posts B and D, as well 'indicated by full and dottedjlines AiI1' I|`ig r,.V 3. The distances between A and E, between E and B and 'between C fand Dare preferably such that the connector 88 may not A4be erroneously positione'd between them.l
lhe'arrangement ot' the connector 88 between B and C as shownin Fig. I places the two magnet coils X. and-Y in series. Thus, assuming that thewcurrent entersat A, it passes through'thejlead 89 to the coil X and passes thence through the lead 90 to the binding post B, thence through the yconnec- 1 the chart device illustrated in Fig. 4, and
the other desirable arrangements are indicated in columns 3, 4 and 5 of the chart.
It it should be desired to energize coil Y alone, in which case the pick-up current would have to be doubled owing to the energization of only half the number of magnet turns (assuming the coils X and Y to be the same in all material respects), connector 88 is placed between the binding post A and C, as shown in column 3 of the chart, in which case the current would pass from A to C and from there through lead 91 to magnet Y and through lead 92 to binding post D.
It is sometimes desirable to connect the magnet coils in multiple, thereby decreasing the resistance through these coils, and to accomplish this two connectors as 88 are employed and arranged as indicated in column 4 of the chart, in which case the current `trom lead 86 divides at A and passes in equal amounts tirst through lead 89 to coil X, thence back through lead 90 to binding post B and thence through the connector E38 to binding post D, the other half of Athe current passing from A to C, thence through lead 91 to coil Y and thence back through lead 92 to binding post D.
There it is desired still further to increase the pick-up current a portion of the current may be shunted through a resistor' R connected to binding posts E and D. Column 5 of the chart shows the arrangement oit' the connectors for this purpose, in which case the current passes from A to G and there divides, one part passing from C to E and from E through the resistor R and passes out at the binding post D, the other part passing through lead 91, through the coil Y and back through lead 92 to the binding post D.
The principal advantages of the currentcontrolling device just described arise from the fact that it is self-contained with the rest of the device, the leads 86 and 87 are always secured to the same binding posts A and D respectively, the various connections can readily be made and with the certainty olf making the proper connections for a given result, and the resistor R, being a iXed part of the device, is always a predetermined and known quantity in the result. lFurthermore, the Vvarious adjustments for current control may be made by a relatively inexperienced person by referring to the diagram or chart such as shown in Fig. 4.
In the chart of Fig. Ll P-U means pick-up and Reh77 means release. The relative current values shown in column 2 and in column 5 are to be understood as being merely suggestive and as indicating the wide range otl adjustment desirable and obtainable in a relay ot the kind described. The actua-l iigures insertable throughout the chart will depend upon the calibration of the instrument, and the particular resistance of the magnet coils and of the resistor R employed.
Vhen it is desired to use one of these relays in service it is only necessary lirst to determine the current available, which we may assume ior instance to be .480 ampere. By reference to the chart in one of the columns marked P-U either this exact strength oi current or one closely approximating it will be found opposite a certain dial reading shown in column l. We may assume that this current value will be found in column 3 of the chart opposite dial reading 8. Thereupon the operator adjusts his coil connections in accordance with the diagram at the top of column 8, and then simply turns the hand wheel until the finder 82, Fig. 2, points to 3 on the dial 80. If the operator should lind that his available current is one which lies between two pickup values as shown by the chart he can by an ordinary method of interpolation determine the precise setting for the dial.
According to these improvements, therefore the relay may be adjusted in an exceedingly brief space of time, without removing it from service, without the use of an auxiliary instrument, and by one who is not especially skilled in the adjustment of devices of this general kind.
Vhile I have thus illustrated and described a highly efficient and desirable embodiment of these improvements I contemplate as being within the present invention various modifications oi' the specilic structure herein disclosed as indicated in the appended claims.
I claim:
1. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of which is controlled by the movement of the armature, for making and breaking an electric circuit, and unitary means for adjustably increasing and decreasing the responsiveness 0i the armature to the magnetic energy and for maintaining substantially a uniform pressure between said contacts at the several adjustments of such responsiveness and when the `magnet is energized at the pick-up current.
2. In a relay, the combination oi an electromagnet, an armature mounted to move in response to the magnetic energy, means iii-- cluding a pair ot' contacts, one oi? which is controlled by the movement'oif the armature, for making and breaking an electric circuit, the magnetic circuit having an air gap to provide reluctance to the magnetic flux, unitary means for adjustably increasing and decreasing the air gap and for maintaining substantially a uniform pressure between saidcontacts at the various adjustments-of theair gap'xand when the magnet'fisenergizedatv pick-up'current', and means `torindicating the relative magnitudes of such increase and decreaseY of thej air gap.
3. In al relay, the combination of an electromagnet, an armature mounted to move in response to the magneticI energy, means including a pair of contacts, one of Which is controlled by the movement of the armature, for making and breaking an electric circuit, unitary means for moving the armature for i adjustably increasing and decreasing the responsiveness of the armature to the magnetic energy whereby the armature will be actuated to close the circuit through said kvcontacts by different values of the current contacts being such that a substantially uni form pressure between the contacts Will be maintained throughout the range of adjustment when the magnet is energized at pickup current.
4. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of cont-acts, one of Which is controlled by the movement of the armature, for making and breaking an electric circuit, and means for simultaneously moving adjustably both contacts and at diierent rates.
5. VIn a relay, the combination of an electromagnet, ank armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of Which is controlled by the movement of the armature, for making and breaking an electric circuit, and means for simultaneously moving adjustably both contacts and the armature, the rate of movement of the contact which is not under the control of the armature being different from the rateof movement of the other contact.
6. In a relay, the combination of an electrogmagnet, an armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of which is controlled by the movement ofthe armature, for making and breaking an electric circuit, and means for simultaneously moving adjustably the armature, the contact controlled thereby, and the other contact, the rate of movement of the armature and the contact controlled thereby being different from the A. rate of movement of the other contact and ture, for making vand, breaking an electric circuit, and means including" athreaded member ,having threads thereon ot" different pitches respectively for siii'iultaneously moving adjustably the armature, andwith'it the contact Acont-rolled thereby, at a predetermined rate and tlie other Contact at a dit- 'terent predetermined rate.
8. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a. pair of contacts, one of which is controlled by the movement of the armature, tor making and breaking an eleotric circuit, means for simultaneously moving adjustably both contacts and at diterent i'ates, and means for indicating the relative adjustment at any time made.
9. In a relay, the combination ot an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of which is -controlled by the movement of the ar mature, for making and breaking an elcotric circuit, means for simultaneously moving adjustably both contacts and the armature and at diiferent rates, and means for indicating the relative adjustment at any time made.
l0. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of which is controlled by the movement of the armature, t'or making and breaking an electric circuit, means for simultaneously moving adjustably the armature, the Contact controlled thereby and the other contact, the rate of such adjustment movement of the armature and of one of said contacts being` the same and being diiierent from that ot the other contact and means for indicatinv' the relative adjustment at any time made.` D
ll. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of contacts, one of which is controlled by -the movement of the armature, tor making and breaking an electric circuit, means including a threaded member having threads thereon of different pitches respectively for simultaneously moving adjustably the armature, and With it the contact controlled thereby, at a predetermined rate and the other contact at a different predetermined rate and means operatively associated with said threaded member for indicating the relative adjustment at any time made.
12. In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair oit' cooperating contacts, one ot' Which is controlled by the movement of the armature, for making and breaking an llO electric circuit, and unitary means for simultaneously moving adjustably both contacts and at different rates.
18, In a relay, the combination of an electromagnet, an armature mounted to move in response to the magnetic energy, means including a pair of `cooperating contacts, one of which is controlled by the movement of `the armature, for making and breaking an electric circuit, and unitary means for simultaneously moving acljustably both contacts and the armature, the rate of movement of one of said contacts being different from that of the armature.
CLINTON O. HARRINGTON.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3153715A (en) * 1962-07-30 1964-10-20 Charles F Weisgerber Switch having variable differential and range adjustment

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3153715A (en) * 1962-07-30 1964-10-20 Charles F Weisgerber Switch having variable differential and range adjustment

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